sin (x_1 + x_2 + ...+ x_n) < sin x_1 + sin x_2 + ,,,+ sin x_n
Source: Polish MO second round 1954 p6
August 29, 2024
inequalitiestrigonometry
Problem Statement
Prove that if x1,x2,…,xn are angles between 0∘ and 180∘, and n is any natural number greater than 1, then sin(x1+x2+…+xn)<sinx1+sinx2+…+sinxn.